kärnanmantelngränsen

The Gutenberg discontinuity, also known as the core-mantle boundary (CMB), is the boundary within Earth that separates the liquid outer core from the solid mantle. It is located approximately 2,900 kilometers (1,800 miles) below the Earth's surface. This boundary is a significant zone of chemical and physical change.

Seismic waves, particularly shear waves, are unable to pass through the liquid outer core, causing a shadow zone on the opposite side of the Earth from an earthquake. The abrupt change in seismic velocity at the Gutenberg discontinuity is a primary indicator of its existence. Variations in the strength and behavior of seismic waves at this boundary provide insights into the complex dynamics of the Earth's interior.

The Gutenberg discontinuity is thought to be a region where significant heat transfer occurs from the outer core to the mantle. This heat flow is a driving force for mantle convection, which in turn powers plate tectonics. The boundary is also believed to be the source of some types of volcanic activity, such as hot spots. Chemical interactions between the core and mantle materials at this boundary may also play a role in the Earth's evolution. The precise nature of the Gutenberg discontinuity is still an active area of research, with ongoing studies using seismology and other geophysical methods to better understand its properties and implications for Earth's processes.